1. Field of the Invention
The present invention relates to a plasma display panel and a method of manufacturing the same, and more particularly to a plasma display panel where a transparent electrode pattern of a display region is also formed on a boundary portion between the display region and a non-display region, and a method of manufacturing the same.
2. Description of the Related Art
A plasma display panel (PDP) is a display device that displays images using a gas discharge phenomenon. The PDP has superior display characteristics, such as display capacity, brightness, contrast, after-image, and viewing angle.
The PDP generates a gas discharge between electrodes within a discharge cell when a driving voltage is applied to the electrodes of the discharge cell. This causes vacuum ultraviolet rays to form and excite phosphors so that visible light can be emitted to realize display images.
The PDP includes a display electrode on the inner surface of a first substrate, an address electrode on an inner surface of a second substrate, and a barrier rib located between the two substrates to form the discharge cell. In the PDP, a discharge gas is filled within the discharge cell.
The display electrode is actually a pair of electrodes. The two electrodes in the pair are called a sustain electrode and a scanning electrode. The sustain electrode and the scanning electrode are located in each discharge cell and are used to generate a sustain discharge. The display electrode and the address electrode are oriented to intersect each other and together serve to select the discharge cell.
Each of the sustain electrode and the scanning electrode is made up of a transparent electrode that is used to generate a surface discharge within the discharge cell and a bus electrode that is used to apply a voltage to the transparent electrode. The transparent electrode is made out of ITO (Indium Tin Oxide) and is located on the first substrate to increase the aperture ratio (i.e., the transmittance of visible light generated within the discharge cell). The bus electrode is made out of a highly conductive metal.
To form the transparent electrode on the front substrate, a photolithography technique or a laser ablation technique can be used. The photolithography technique includes the steps of applying an ITO material to the first substrate by sputtering, patterning the ITO material to form the transparent electrode pattern, applying the metal conductive material onto the transparent electrode pattern, and patterning the metal conductive material to form the bus electrode. Since the photolithography technique requires photoresist coating, photoresist patterning and then an etching process, the photolighography technique is very time consuming, is complicated and is expensive. In contrast, the laser ablation technique is advantageous in that it may reduce the number of process steps and reduce the processing time in forming the transparent electrode pattern. Further, laser ablation can enhance the straightness of the end portion of the transparent electrode pattern formed when patterning the ITO layer.
The transparent electrode, when produced by the laser ablation technique, is formed by coating the ITO layer on the inner surface of the first substrate, and then patterning the ITO layer in the display region of the PDP. Since gas discharge does not occur in the non-display region of the PDP, the bus electrode and the transparent electrode are not formed in the non-display region, and thus there is no need to pattern the transparent electrode material deposited in the non-display region. Therefore, the ITO material applied to the non-display region is removed by laser ablation, resulting in an increase the process time. What is needed is an improved design for a PDP and an improved technique of making the PDP that is less complicated and further reduces processing time beyond that of the above laser ablation technique.